FUNCTION

When your window is an AppWindow, i.e. you have set the
MUIA_Window_AppWindow attribute to TRUE, you will be able to get AppMessages by listening to MUIA_AppMessage. Whenever an AppMessage arrives, this attribute will be set to a pointer to that message.

MUIA_AppMessage is object specific. You can e.g. set up different notifications for different objects in your window, they will only get exectued when icons are dropped over the specific object.

If you wait on MUIA_AppMessage with a window object, your notify will always get executed when icons are dropped on the window.